Circuit card retaining system

ABSTRACT

An add-on circuit card retention apparatus is disclosed that includes an add-on circuit card defining a reference plane and having a first connector, a second circuit card having a second connector for mating with the first connector, and a clip assembly for releasably securing the add-on circuit card to the second circuit card. The clip assembly includes a first catch member located on the add-on circuit card and a second catch member being located on the second connector. The first catch member has a first catch surface generally lying in a plane forming a first catch member angle with respect to the reference plane of less than 90 degrees. The second catch member has a second catch surface generally lying in a plane forming a second catch member angle with respect to the reference plane of less than 90 degrees when the first connector of the add-on circuit card is in a mated condition with the second connector

FIELD OF THE INVENTION

The present invention generally relates to the field of circuit cardretention where a printed circuit card is inserted into a connector andis retained by a secondary component which impedes inadvertentdisengagement of the card, or the like.

BACKGROUND OF THE INVENTION

Printed circuit cards with edge connectors or other forms of connectorsare widely used in many electronic products. These cards may be used toconfigure additional capability to an otherwise standard system. Forexample, in many Personal Computer (PC) systems, various card standardsexist to allow the manufacturer or end user to add features andcapabilities to the computer. These standards include, but are notlimited to, PCI (Personal Computer Interconnect) cards, ISA (IndustryStandard Adapter) cards, Micro-Channel cards, Card Bus cards, PCMCIAcards and newer standards, such as 3GIO (3^(rd) Generation I/O) cards.Some of these cards have connectors mounted on the edge that mates witha connector on a different printed circuit card within the PC. Some ofthese cards have contacts, called fingers, on their edge, collectivelycalled edge connectors. These cards insert into connectors mounted onanother printed circuit card within the system or PC, such as amotherboard.

In general, these upgrade cards are sometimes held in place by a bracketat one end of the card. Usually, this bracket is the same bracket thatadditionally has connectors to interface with external components. Forexample, if the upgrade card is a Video Graphics Card, then the bracketmay contain a graphics port, possibly utilizing the Video GraphicsAdapter (VGA) standard. Even with this bracket and the use of a screw,there exists an industry problem whereas these upgrade cards becomeunseated from the connector on the second printed circuit card causingsystems to malfunction or to not operate. Shock and vibration can causethe upgrade card to at least partially lift out of the connector andlose contact on one or more of its fingers. A prevalent symptom of thishappening are PC systems that fail when delivered to customers due toshipping shock and vibration, exhibiting symptoms such as “no-video”when the graphics adapter becomes loose or “no-modem” when the modembecomes loose.

In the prior art, several attempts have been made to hold the upgradecards in place, especially during shipping. Some attempts include astrap passing over the card, and positioning a stop material on theequipment cover that pushes down on the card to keep it in place.

Another approach has been to employ a rigid clip that attempts to lockthe card to the connector that it is inserted into. One example of sucha rigid clip system 100 is depicted in FIG. 1 of the drawings, whichshows an adapter card 110 with a rigid clip assembly 140, 150 and 160.The rigid clip assembly 140, 150 and 160 consists of three components: asupport member 140; a riser member 150, and a connector interface member160. The support member 140 is affixed to the adapter card 110. When theadapter card is fully mated with connector 120, the interface member 160of the rigid clip assembly engages a lip 130 of a connector 120 intowhich the adapter card is inserted, and shouldn't easily separate fromconnector 120 when shock or vibration occurs. The connection interfacemember 160 and the lip 130 each have a contacting surface, and thecontacting surfaces of the respective parts contact each other when theinterface member 160 engages the lip 130. Each of the contactingsurfaces lies in a plane that is oriented perpendicular to the surfaceof the adapter card 110, so that simple lateral movement of theinterface member 160 with respect to the lip 130 releases the member 160from the lip 130 and the adapter card 110 is free to move out of theconnector 120.

This known clip structure is somewhat effective in reducing thelikelihood that the adapter card 110 will become inadvertently dislodgedfrom the connector 120. However, since simple lateral movement of alower portion of the riser member 150 that carries the interface member160 can release the member 160 from the lip 130 (which can result simplyfrom flexing of the support member 140), there is still an appreciablechance that jostling during shipping or other movement of the PC willresult in the adapter card 110 being dislodged from the connector 120.

The present invention is an improvement upon the latter structure thatprovides greater resistance to inadvertent release of the adapter cardfrom the connector.

SUMMARY OF THE INVENTION

The present invention is directed to a clip assembly that is attached tothe upgrade or option card, whereas the clip assembly is coupled to thesame connector that the upgrade or option card is inserted into andwhereas the clip assembly holds the upgrade or option card in place, andimpedes the upgrade or option card from moving out of the connector whenshock and vibration occur, while still being releasable by fingerpressure applied to the appropriate location on the clip assembly.

The prior art structures rely upon friction alone between the clipassembly and a lip formed on the connector to hold the card in placeSince both the clip assembly and the lip are often made from plastic,the amount of friction present therebetween is usually minimal, and thisoften allows the clip assembly to slip out of engagement with the lipunder certain shock or vibration scenarios. The present inventionimproves upon the prior art by incorporating an angled first catchsurface at the point where the clip assembly engages an angled secondcatch surface on the connector so that the clip assembly is engaged withthe connector, and in turn the upgrade or option card on which the clipassembly is mounted is more effectively held in engagement with theconnector.

It is to be understood that both the foregoing general description andthe following detailed description are exemplary only and are notrestrictive of the invention as claimed. The general functions of thisinvention may be combined in different ways to provide the samefunctionality while still remaining within the scope of this invention.Various combinations of connectors and upgrade cards may be used withoutveering from the intent of this invention. Throughout this description,the term upgrade card is used to represent a printed circuit card thathas a connector or fingers that mate with a connector or fingers on adifferent printed circuit card. This type of card is known to oneskilled in the art as an option card, a daughter card, an option card,an upgrade card, or the like. Likewise, the printed circuit that has aconnector or fingers that the upgrade card plugs into may be known as a“motherboard,” but this invention is not limited by this.

BRIEF DESCRIPTION OF THE DRAWINGS

The numerous advantages of the present invention may be betterunderstood by those skilled in the art by reference to the accompanyingfigures in which:

FIG. 1 shows a side view of the prior art.

FIG. 2 shows a side view of an adapter card according to the presentinvention with the improved rigid clip.

DETAILED DESCRIPTION

Reference will now be made in detail to the presently discussedembodiment of the invention, an example of which is illustrated in theaccompanying drawing.

Referring now to FIG. 2, a retaining system 200 in accordance with thepresent invention is shown. The retaining system 200 may be implementedon a first circuit card, which may be described as an add-on, or anadapter, card 210. The adapter card 210 typically includes a surface orface 212 that may generally define a reference plane. The adapter card210 typically has an edge portion or region that forms a first connector214, and this first connector portion of the card 210 may be providedwith a plurality of electrical contacts. A second circuit card 216,which in some embodiments of the invention forms a motherboard of acomputer, includes a second connector 220. The first connector 214 ofthe adapter card 210 may be mated with the second connector 220 byinserting the first connector 214 into a slot formed in the secondconnector 220 in a movement that is generally parallel to the referenceplane.

The retaining system 200 includes a substantially rigid clip assembly235. The clip assembly 235 may include three components: a supportmember 240, a riser member 250, and a first catch member 260.Optionally, all three components of the clip assembly 235 may be moldedas one piece from the same material, or may be separate components thatare bonded together. The support member 240 of the clip assembly 235 isaffixed to the adapter card 210. The support member 240 may be attachedby adhesive, glue, rivet, screw or any means known to the industry.

The second connector 220 on the second circuit card 216 has a secondcatch member 230 that engages with the first catch member 260 of theclip assembly 235 when the first connector 214 is fully seated in thesecond connector 220. The second catch member 230 may extend along, andgenerally parallel to, a length of the second connector 220.

In a significant aspect of the invention, the first catch member 260 hasa first catch surface 262 that is oriented at a first catch member anglethat may be measured with respect to various structures, including withrespect to the reference plane of the adapter card 210 or with respectto an extent of the riser member 250. While the reference plane of theadapter card 210 and the riser member 250 may often be substantiallyparallel, the first catch member angle as referred to herein will bemade in reference to the reference plane of the adapter card 210, or aplane oriented parallel to the reference plane which would result in thesame relative angle measurement.

In exemplary embodiments of the invention, the first catch member angleis an interior angle of less than 90 degrees. The first catch memberangle may be different than that depicted in FIG. 2. The first catchmember angle may be relatively large, for example, 89 to 85 degrees, orit may be anywhere in the range of slightly less than 90 degrees to aslittle as 70 degrees. Some exemplary ranges for the first catch memberangle: 89 degrees to 85 degrees; 85 degrees to 80 degrees and 80 degreesto 75 degrees. In some instances, the present invention may beconfigured with the first catch member angle measuring less than 70degrees to help prevent the adapter card 210 from separating from itsconnectors due to extreme shock or vibration.

In another significant aspect of the invention, the second catch member230 has a second catch surface 232 that is oriented at a second catchmember angle with respect to the reference plane of the face 212 of theadapter card 210. The second catch surface 232 is thus positioned suchthat when engaged with the first catch surface, the first catch member260 cannot easily slide off of the second catch member 230 merely byovercoming any friction between the catch surfaces 232, 262. The secondcatch member angle associated with the second catch member 230 may besubstantially the same as the first catch member angle of the firstcatch member 260 so that the orientations of the surfaces 232, 262 arecomplementary. Optionally, the second catch member angle of the secondcatch surface 232 may be slightly less than the first catch member angleof the first catch surface 262 to promote a better grip between thesecond catch member 230 and the first catch member 260.

Once the first connector 214 of the adapter card 210 is sufficientlyinserted into the second connector 220 (such as, for example, to achieveelectrical communication between the contacts of the first and secondconnectors), the first catch member 260 rests next to the second catchmember 230 of the second connector 220. During the installation process,placing slight downward pressure on the riser member 250 causes thesupport member 240 to flex slightly, allowing the leading edge of thefirst catch member 260 to pass beyond the leading edge of the secondcatch member 230 and mate appropriately. Once in this position, thefirst catch member 260 doesn't easily separate from the second catchmember 230 when shock or vibrations occur.

Significantly, the orientation of the first catch surface 262 at a firstcatch member angle of less than 90 degrees and the second catch surface232 at a second catch member angle of less than 90 degrees generallycreates a hooked (and generally interlocked) relationship or conditiontherebetween when the first catch member 260 and the second catch member230 are engaged with each other and the first connector 214 is fullyseated in the second connector 220. This hooked or interlocked conditionof the first catch member 260 and the second catch member 230 is notundone simply by lateral outward movement of the first catch member 260with respect to the second catch member 230, such as might easily occurduring jostling experienced by the computer during shipping. To undo thehooked condition of the first catch member 260 and the second catchmember 230 requires that the first catch member 260 not only movelaterally outward from the second catch member 230, but also in thegeneral direction of the second connector 220 and generally toward themotherboard 216 on which the second connector 220 is typically mounted.In this way, the shape of the first catch member 260 and the secondcatch member 230 (and the respective orientations of the first 262 andsecond 232 catch surfaces) may actually force the riser member 250 toalso move toward the second connector 220, as well as, depending uponthe rigidity of the support member 240, the adapter card 210 itself.Thus, dislodging of the second catch member 260 from the first catchmember 260 may require that the first connector 214 of the adapter card210 itself move deeper into the slot of the second connector 220. As aresult, accidental dislodgement of the first connector 214 of theadapter card 210 from the second connector 220 is made more difficult,and less likely. Moreover, movement of the adapter card 210 outwardlyfrom the second connector 220 actually increases or intensifies thehooked relationship between the first catch member 260 and the secondcatch member 230, leaving the first 260 and second 230 catch membersmore strongly engaged.

The second catch member 230 can be made of the same material as the caseof the second connector 220, or it may be fabricated separately andaffixed in various ways including an adhesive or bonding agent. Thesupport member 240 may be fabricated of a material such as plastic ormetal that is somewhat flexible yet after releasing pressure, restoresto substantially its original shape, thereby allowing pressure to beexerted to engage the catch and after pressure is released, the firstcatch member 260 raises so that it fully engages with the second catchmember 230.

Although the invention has been described with a certain degree ofparticularity, it should be recognized that elements thereof may bealtered by persons skilled in the art without departing from the spiritand scope of the invention. It is believed that the improved circuitcard retaining system of the present invention and many of its attendantadvantages will be understood by the forgoing description, and it willbe apparent that various changes may be made in the form, constructionand arrangement of the components thereof without departing from thescope and spirit of the invention or without sacrificing all of itsmaterial advantages, the form herein before described being merely anexplanatory embodiment thereof, and further without providingsubstantial change thereto. It is the intention of the claims toencompass and include such changes.

1. An add-on circuit card retention apparatus comprising: an add-oncircuit card having a face generally defining a reference plane, saidadd-on circuit card having a first connector; a second circuit cardhaving a second connector for mating with said first connector toprovide electrical contact between said add-on circuit card and saidsecond circuit card; a clip assembly for releasably securing said add-oncircuit card to said second circuit card, said clip assembly comprising:a first catch member located on said add-on circuit card and extendingtowards said second connector, said first catch member having a firstcatch surface, said first catch surface generally lying in a planeforming a first catch member angle with respect to said reference planeof less than 90 degrees; and a second catch member being located on saidsecond connector and extending along said second connector, said secondcatch member having a second catch surface extending away from saidsecond connector, said second catch surface generally lying in a planeforming a second catch member angle with respect to said reference planeof less than 90 degrees when said first connector of said add-on circuitcard is in a mated condition with said second connector.
 2. An add-oncircuit card retention apparatus according to claim 1, wherein said clipassembly further includes a first member extending from said add-oncircuit card and a second member extending from said first member to aposition near said second connector when said first connector of saidadd-on circuit card is mated with said second connector of said secondcircuit card, said first catch member being mounted on said secondmember.
 3. An add-on circuit card retention apparatus according to claim1, wherein said first catch member angle measures between 89 degrees and70 degrees.
 4. An add-on circuit card retention apparatus according toclaim 1, wherein said second catch member angle measures between 89degrees and 70 degrees.
 5. An add-on circuit card retention apparatusaccording to claim 1, wherein said first catch member angle issubstantially equal to said second catch member angle.
 6. An add-oncircuit card retention apparatus according to claim 1, wherein saidsecond connector has a side, and said second catch member is located onsaid side of said second connector.
 7. An add-on circuit card retentionapparatus according to claim 1, wherein said clip assembly issubstantially rigid.
 8. An add-on circuit card retention apparatusaccording to claim 1, wherein said second circuit card is a personalcomputer motherboard.
 9. An add-on circuit card retention apparatusaccording to claim 1, wherein said first connector is a printed circuitcard edge connector and said second connector conforms to the PersonalComputer Interconnect (PCI) standard.
 10. An add-on circuit cardretention apparatus according to claim 1, wherein said first connectoris a printed circuit card edge connector and said second connectorconforms to the Industry Standard Adapter (ISA) standard.
 11. An add-oncircuit card retention apparatus according to claim 1, wherein saidfirst connector is a printed circuit card edge connector and said secondconnector conforms to the next generation interconnect standard known as3GIO.
 12. A method for securing an add-on circuit card with a firstconnector in a mated relationship with a second connector, said add-oncircuit card having a clip assembly, said clip assembly including afirst catch member with a first catch surface thereon mounted on saidadd-on circuit card and a second catch member with a second catchsurface formed thereon on said second connector, said first catchsurface being oriented at an acute angle with respect to a face of saidadd-on circuit card and said second catch surface being oriented at anacute angle with respect to said face of said add-on circuit card whensaid connectors are in a mater condition, comprising: inserting saidfirst connector of said add-on circuit card into said second connector;seating said first connector of said add-on circuit card fully into saidsecond connector; exerting pressure on said clip assembly such that saidfirst catch member of said clip assembly extends just past said secondcatch member of said second connector; maneuvering said first catchsurface of said first catch member so that said first catch surfacealigns with said second catch surface of said second catch member ofsaid second connector; and releasing pressure on said clip assembly suchthat said first catch surface of said first catch member on said firstconnector contacts said second catch surface of said second catch memberon said second connector to thereby retain said first connector in saidsecond connector.
 13. A method according to claim 12, wherein saidsecond connector is mounted on a second circuit board, and said secondcircuit board comprises a personal computer motherboard.
 14. A methodaccording to claim 12, wherein said first connector is a printed circuitcard edge connector and said second connector conforms to the PersonalComputer Interconnect (PCI) standard.
 15. A method according to claim12, wherein said first connector is a printed circuit card edgeconnector and said second connector conforms to the Industry StandardAdapter (ISA) standard.
 16. A method according to claim 12, wherein saidfirst connector is a printed circuit card edge connector and said secondconnector conforms to the next generation interconnect standard known as3GIO.
 17. A method according to claim 12, whereas said clip assembly isfastened to said add-on circuit card by an adhesive.
 18. A methodaccording to claim 12, whereas said clip assembly is fastened to saidadd-on circuit card by welding.
 19. A method according to claim 12,whereas said clip assembly is fastened to said add-on circuit card by afastener.
 20. A method according to claim 12, wherein said first catchsurface has substantially the same angle as said second catch surface.21. An add-on circuit card retention apparatus according to claim 1,wherein said second catch member angle is slightly less than said firstcatch member angle.
 22. An add-on circuit card retention apparatusaccording to claim 1, wherein said first catch member extends outwardlyfrom the face of said add-on circuit card, and wherein said secondconnector has a side corresponding to the face of said add-on circuitcard when said first connector of said add-on circuit card is mated withsaid second connector of said second circuit card, said second catchmember being located on said side of said second connector.
 23. Anadd-on circuit card retention apparatus according to claim 1, whereinsaid clip assembly further includes a first member extending from saidadd-on circuit card and a second member extending from said first memberto a position near said second-connector when said first connector ofsaid add-on circuit card is mated with said second connector of saidsecond circuit card, said first catch member being mounted on saidsecond member in a manner such that said first member forms a fulcrumfor said second member and such that application of force to a portionof said second member tends to move said first catch member out ofengagement with said second catch member when said first connector ofsaid add-on circuit card is mated with said second connector of saidsecond circuit card.